方法
- 与 方法 相关的网络例句 [注:此内容来源于网络,仅供参考]
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Chapter 8: We discuss the acceleration of multigrid by Krylov subspace approaches, and recognize the reason for slow convergence of algebraic multigrid methods is that error reduction is significantly less efficient for some very specific error components which may cause a few eigenvalues of the algebraic multigrid iteration matrix to be considerably closer to 1 than all the rest. However, the eigenvectors belonging to the few isolated eigenvalues can be expected to be typically captured after only a few conjugate gradient iterations, which accelerate algebraic multigrid algorithms. Theoretical analysis and numerical results of some practical problems show the iterant recombination accelerates algebraic multigrid convergence.
第八章:先介绍用Krylov子空间迭代法加速一般多重网格方法收敛的基本框架,然后紧紧抓住引起代数多重网格方法收敛减慢的根本原因往往是误差减小对几个特别的误差分量不明显,这导致代数多重网格方法的迭代矩阵的几个特征值接近于1,而共轭梯度方法则能比较典型地捕捉属于孤立特征值的特征向量,从而推导出有效的共轭梯度加速算法和程序实现,不仅从一些具体的实际应用例子的数值结果去验证迭代复合加速收敛的效果,而且还从理论上分析了预处理共轭梯度法加速代数多重网格法收敛的机理。
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To evaluate which combinations of preprocessing and differential expression method perform well, we consider 4 popular preprocessing methods (MAS 5.0, RMA ,dChip and PDNN) and 5 popular differential expression methods (fold-change, two sample t-test, SAM, EBarrays and limma).
为了评估各种预处理方法与表现量差异方法组合的表现,我们考虑了四种常用的预处理方法:MAS 5.0、RMA、dChip及PDNN,与五种常用的表现量差异方法:fold-change、two sample t-test、SAM、EBarrays及limma。
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Abstract] objective to summarize the methods and experience and analysing of curative effects of open operation combined eswl treating renal staghorn calculi.methods therapeutic results of 8 cases of renal staghorn calculi were analysed retrospectively.results the lithous horn of 8 cases were broken by eswl before operation,then the renal calculus were removed by pyelolithotomy or extended pyelolithotomy.conclusion the method was a good choice of renal staghorn calculi with high stone-free rate,little trauma and less complication.
摘要] 目的总结开放性手术结合eswl治疗鹿角状肾脏结石方法经验并进行疗效分析。方法回顾分析了8例鹿角状肾脏结石患者的治疗结果。结果 8例患者术前eswl将结石角粉碎,然后应用肾盂切开或肾窦扩大切开手术取出肾盂和肾盏内结石。结论该方法对于鹿角状肾脏结石治疗,结石取净率高,对肾脏损伤小、并发症少,是较为适合的方法。
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Dynamic Mechanical Analysisis one ofdynamic thermal machinism analyse technology,measuring changes of viscoelastical parameters alongwith temperature or frequency under vibrative load.DMA estimates various performances of viscoelasticalmaterial,using rheological index.
简要阐述了DMA的原理,论述了用DMA方法进行沥青材料性能研究的优越性,结合具体实例阐述该方法在研究沥青及沥青结合料的粘弹性、高温性能、疲劳性能和低温性能等方面的应用,以及DMA方法用于测定沥青零剪切粘度的方法介绍。
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First, this paper gives an introduction of some methods of unequal probability sampling, their estimators and variance estimators, including sampling with pps with replacement, methods of sampling without replacement suggested by Brewer, Durbin, Sampford , Des Raj , Murthy , Rao-Hartley-Cochran. Then, at the basis of Rao and Bayless's study , we consider that population can be splited two random subpopulations, which are respectively drawn from different infinite super-populations, and compare the stabilities of estimators of the methods that given above.
本文首先从理论上介绍了若干种不等概率抽样方法,它们的估计量、估计量的方差及其估计,其中包括有放回PPZ及PPS抽样,不放回不等概率抽样中的Brewer、Durbin、Sampford、Des Raj,Murthy、Rao-Hartley-Cochran等人的方法;其次,在Rao和Bayless两人就样本单元数n=2的情形对上述抽样方法进行比较的基础上,将总体随机地分成两个子总体,视每个子总体取自不同的线性超总体,在文中,我们利用计算机实现随机分组,并通过画图比较各方法估计量的稳定性,结果表明,对变异系数C.V。
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First, this paper gives an introduction of some methods of unequal probability sampling, their estimators and variance estimators, including sampling with pps with replacement, methods of sampling without replacement suggested by Brewer, Durbin, Sampford , Des Raj , Murthy , Rao-Hartley-Cochran.Then, at the basis of Rao and Baylesss study , we consider that population can be splited two random subpopulations, which are respectively drawn from different infinite super-populations, and compare the stabilities of estimators of the methods that given above.
本文首先从理论上介绍了若干种不等概率抽样方法,它们的估计量、估计量的方差及其估计,其中包括有放回PPZ及PPS抽样,不放回不等概率抽样中的Brewer、Durbin、Sampford、Des Raj,Murthy、Rao-Hartley-Cochran等人的方法;其次,在Rao和Bayless两人就样本单元数n=2的情形对上述抽样方法进行比较的基础上,将总体随机地分成两个子总体,视每个子总体取自不同的线性超总体,在文中,我们利用计算机实现随机分组,并通过画图比较各方法估计量的稳定性,结果表明,对变异系数C.V。
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Moreover, the actual allele frequency of most varieties deviates far from Hardy-Weinberg equilibrium. All PPB、na 、I、h、Gi and Fst have proved to be the references to elucidate that ISSR is a most powerful tool to analyze genetic diversity, compared with the RAPD marker and the allozyme marker is less strong ordinally. We could divided the 70 samples into A, B, C, D and E five groups using three methods according to genetic distance clustering. There is a bit displacement for few varieties in different clustering maps, but the most are similar to morphological analysis despite that there is still a great difference among cultivars in the same one group. The above results imply that the three methods have the different sensitivity and resolution in genetic distance analysis of close varieties. The Mantel test indicates that the results from the three kinds of markers have the significant correlation, which demonstrates that the number of the used three kinds of markers is enough to exactly detect the diversity of all 70 samples to ideal extent. And these methods can be used to evaluate the diversity of the whole group using the miscellaneous samples instead of the individual sample, of the Gerbera jamesonii are mainly from tissue culture plants. In conclusion, the above study results provide a reference for the application of three kinds of molecular markers to molecular marker-assisted breeding of flower. 2. The genetic diversity among the eight introduced cut-flower varieties of Ranunculus asiatica was analyzed by the ISSR markers. Based on the genetic clustering tree, all the colorful flower varieties are clustered into one group, and the white flower varieties into another group. Moreover, among the former group the yellow flower varieties are clustered into one sub-group, and the reddish flower varieties, such as rose color, pink, nacarat, are clusetered into another sub-group.
由三种分子标记的分析结果可以看出,等位基因平均值、观察杂合度、Fis值、Fit值皆较高,表明非洲菊等位基因较丰富,杂合基因偏多,且绝大部份品种的实际等位基因频率在品种内偏离了Hardy-Weinberg equilibrium;PP8、na、Ⅰ、h、Gi及Fst皆表明,ISSR检测遗传多样性的能力最强,其次是RAPD,等位酶最低;根据遗传距离进行聚类,三种方法都把70个品种分成A、B、C、D、E五个大组,每一组中除少数品种发生位移外,大部份品种分类结果相似,且与形态分析结果有相似性,但在每一组中,品种间的聚类差别较大,表明这三种方法在近距离品种间检测遗传变异时灵敏度及分辨力不同;Mantel检测表明,三种标记的分析结果有显著相关性,表明所用的三种分子方法的标记数量已经可以相对无偏地检测到70个品种间遗传变异;非洲菊为组培苗,三种标记的检测结果皆表明,混合样品可以作为个体样品的代表,对整个居群的遗传多样性进行评价;这些研究结果可为三种分子标记方法在花卉分子辅助育种中的进一步应用提供借鉴。
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Test evaluation method of threshold stress of environmental cracking usually adopts NACE method A, refers to the NACE Standard Tensile Test. This test and its relevant data handling are introduced in this paper.
环境断裂临界应力的试验评价方法通常采用NACE方法A即NACE标准恒载荷延伸试验方法,对该方法及相关的数据处理作了介绍。
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Density Functional Theory method was used to optimize the geometries of 209 PCDE molecules, 209 PBDE molecules and 75 PCDD molecules at the B3LYP/6-31G* level. Using computed structural parameters as theoretical descriptors, the forward stepwise multiple regression technique was adopted to obtain QSPR models of environmental partition properties for these POPs by using GQSARF 2.0 and SPSS12.0 for windows programs. The obtained QSPR models are as follows:(1) QSPR models for predicting subcooled liquid vapor pressure, n-octanol/water partition coefficients lgK_(ow and subcooled liquid water solubilities -lgS_(w,l of PCDEs, of which correlative coefficients (R~2) are 0.988, 0.958 and 0.959 and the root-mean-square-error of estimation are 0.134, 0.116 and 0.327 respectively.(2) QSPR models of lgPL and n-octanol/air partition coefficients lgK_(oa for PBDEs, which both contain three structural parameters. The values of R2 for the two models are both 0.997 while the values of RMSEE are 0.073 and 0.062 respectively.(3) QSPR models of lgKow and–lgS_ for PCDEs, which both have one variable (mean molecular polarizability,α). The values of R~2 for the two models are 0.978 and 0.866 and the values of RMSEE are 0.300 and 0.270 respectively.(4) The molecular structures of 24 substituted naphthaline compounds were optimized using Hartree-Fock and DFT methods at four different levels and the same means was used to obtain four three-parameter (EHOMO, q~+ andα) QSPR models of lgK_. The model at the HF/6-311G** level is the best one of which R2 is 0.9662 and RMSEE is 0.380.(5) QSPR study for environmental partition properties of PCDEs was also performed using position of Cl substitution method in which simple parameters of substitution position were taken as descriptors. The multiple linear regression was performed with GQSARF 2.0 and SSPS 12.0 for windows programs to obtain QSPR models of lgP_L, lgK_ and–lgS_ for PCDEs of which R~2 are 0.991, 0.983 and 0.965 and RMSEE are 0.311, 0.100 and 0.300 respectively.
采用密度泛函理论方法在B3LYP/6-31G*水平上对PCDEs、PBDEs和PCDDs的分子结构进行了全优化计算,以计算得到的量子化学参数作为理论描述符,采用GQSARF 2.0和SPSS 12.0 for windows统计程序进行正向逐步回归分析,建立了这些POPs的环境分配性质的QSPR模型:(1) PCDEs的过冷液体蒸汽压、正辛醇/水分配系数lgK_(ow和水溶解度-lgS_(w,l的QSPR模型,这3个QSPR模型的相关系数(R2)分别为0.988、0.958和0.959,估计的均方根误差分别为0.134、0.116和0.327;(2) PBDEs的lgPL和正辛醇/空气分配系数lgK_(oa的QSPR模型,这两个模型都包含三个分子结构参数,其R~2都为0.997,RSMEE分别为0.073和0.062;(3) PCDDs类化合物的lgK_和-lgS_w的QSPR模型,两个模型都只含一个变量,其R~2分别为0.978和0.866,RSMEE分别为0.300和0.270;(4)采用Hartree-Fock和DFT方法,在4种不同水平上优化计算了24个取代萘系列化合物的分子结构,采用上述同样的方法分别建立了四种水平上的三变量lgK_模型,通过比较得到,在HF/6-311G**水平计算得到的模型最好,R为0.966,RSMEE为0.380;(5)同时,采用氯原子取代位置方法对PCDEs的环境分配性质进行QSPR研究,建立了PCDEs的lgPL、lgK_和-lgS_的QSPR模型,其R~2分别为0.991、0.983和0.965,RSMEE分别为0.110、0.100和0.300。
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Here the theory and the parameters and the assessment method of DOW are introduced. The design method and the realization of oriented object software assessment system are mainly introduced, the nodi of constructing assessment system are analyzed, and the improving ideas are also put forward.
本文介绍了道氏评价方法的工作原理和方法中各个性能参数及其评价方法,着重阐述了面向对象的软件评价系统的设计方法和实现过程,分析了构造评价系统的难点,并提出了改进评价系统的想法。
- 推荐网络例句
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And discuss some key point of integrated management system design, include hazard identification and risk assessment and risk control in the occupational health and safety management, the measure of satisfaction target of customer, the flawlessness of law system, the integration of the integrated management system and enterprise standardization system, unify lead institution and work orgnization, integreted internal audit and integrated management review.
同时,论述了一体化管理体系构建中的几个主要问题,包括职业健康安全管理中的危险源辨识、风险评价和风险控制、顾客满意度的科学监测、法律、法规体系的完善、一体化管理体系与企业标准化体系的有机结合、统一的领导机构和工作机构、一体化的内部审核和管理评审。
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Deepwater Taranaki is investigated for its petroleum potential, using all available seismic data tied to shallow-water wells.
运用与浅水井相关的现有全部震波探测数据考察了深海区塔拉纳基盆地的油藏前景。
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If you're huffing and puffing at any point during the run, slow down and make sure you can take deep breathes.
如果你任何时候在跑步过程中气喘如牛,降低速度并且确保你能够深呼吸。